1. Field of the Invention
The present invention relates generally to endoscopic apparatus and methods of using the same, and particularly to such apparatus and methods for treatment of the prostate.
2. Description of the Prior Art
It is generally known to use endoscopic apparatus for treatment of urinary tract problems. Typically such devices have been particularly constructed for treatment of the interior of the bladder. Such devices are generally referred to as cystoscopes.
More recently, techniques have been developed using a laterally firing laser for treatment of the prostate, and particularly for treatment of a condition generally known as benign prostatic hypertrophy. This condition involves the swelling of the prostate which tends to close off the prostatic urethra which passes therethrough. In laser treatment of this condition, a laterally firing laser tip is placed within the prostatic urethra and directs a laser beam against the inner wall of the prostate.
To date, such techniques have involved the use of standard cystoscopes which have a number of shortcomings since they were not designed for this usage. A standard cystoscope typically includes a hollow outer tube the distal end of which is open and a lateral portion of which is open and communicated with the open distal end. The laterally firing laser tip is run through the cystoscope and extends out the open end of the cystoscope.
These prior art techniques of laser treatment of benign prostatic hypertrophy are described in Costello et al., "Nd:YAG Laser Ablation of the Prostate as a Treatment for Benign Prostatic Hypertrophy", Lasers in Surgery and Medicine 12:121-124 (1992).
Due to the contracted swollen nature of the prostate when the patient is suffering from benign prostatic hypertrophy, the prostatic urethra therethrough may be essentially completely closed and thus it becomes difficult to place the fiber tip in position to treat the inner wall without having the tip actually engage surrounding tissue. If the tip engages surrounding tissue, this can create difficulties in several ways. If the reflecting surface of the tip touches surrounding tissue, it may become covered with foreign matter so that the tip does not function properly. Also, for maximum operational efficiency, the tip should be spaced from the tissue surface being treated. Also, contact of the tip with tissue while the laser is firing may cause the tip to adhere to the tissue.